-LRB- CNN -RRB- -- A spokesman for Somalia 's Islamic party , a militant group in the horn of African nation , has confirmed that the group has merged with the brutal and more hard-line group of Al Shabaab .

The spokesman , Mohamed Osman Arus , told the local media in a news conference that his group has essentially been absorbed by Al Shabaab .

`` We , the Islamic party , have decided to join Al Shabaab both militarily and principally and the reason is , we want to combine our force and fight against the forces of the transitional government and those of the African union , '' said Arus .

Arus said the group 's leader , Sheikh Hassan Dahir Aweys , who is on U.N. terror watch list , is among those to have joined Al Shabaab and there will be no Islamic party structure any longer .

Members from Al Shabaab are seen to be taking control of all positions previously held by the Islamic party both in and around Mogadishu , according to residents in the capital .

Al Shabaab and Hiz bul Islam , as the Islamic party is locally known , have fought bitterly in some parts of southern Somalia . The two groups have struggled for control of the lucrative port city of Kismayo .

In all the cycles of fighting , it was the Islamic party or Hiz bul Islam who lost , according to observers .

Journalist Mohamed Amiin Adow contributed to this report

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Militant party says it is joining with Al Shabaab

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The party , known locally as Hiz bul Islam , is being absorbed by harder-lined group

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The party had been on the losing side in struggles with Al Shabaab